The most frequently detected MARs and therein located potential target genes, which were observed in ≥10% of both BCP-ALL subtypes, were 12p13.2/ETV6 (27%; 16/60), 9p21.3/CDKN2A (23%; 14/60), 9p13.2/PAX5 (22%; 13/60), 4p16.3/NSD2 (17%; 10/60), 11p12/RAG2/IFTAP (17%; 10/60), 20p12.2/MKKS/SLX4IP (17%; 10/60), 3q13.2/CD200/BTLA (15%; 9/60), 9p13.2/ZCCHC7 (13%; 8/60), and Xq25/STAG2 (12%; 7/60). The gene discussed is RAG2; the disease is acute lymphoblastic leukemia.